The goal of operational Business Intelligence (BI) is to help organizations improve the efficiency of their business by giving users information that can be used to make better operational decisions, aligning day-to-day operations with strategic goals. Operational BI reporting contributes to this goal by embedding analytics and reporting information into workflow applications so that the business user has information (e.g., contextual and business data) on which to base a variety of decisions. The creation and querying of customized virtual database schemas over a set of distributed and heterogeneous data sources can provide input to operational BI reports.
Sometimes operational BI reporting applications increase the complexity of source to target mapping defined between source data and virtual databases, resulting in the execution of “mega queries” (e.g., queries with upwards of 1,000 tables in their FROM clause). Mega queries are not supported today by many commercial database systems, including Oracle, DB2, SQL Server and others. Academic research results in the published literature also do not provide solutions for the support of mega queries.